Guerrero-Esteo M, Ruiz-Velasco N, Muñoz M, Teixidó J
Centro de Investigaciones Biológicas, Departamento de Immunología, Velázquez, Madrid, Spain.
FEBS Lett. 1998 Jun 5;429(1):123-8. doi: 10.1016/s0014-5793(98)00576-6.
The N-terminal region of the alpha integrin subunits is predicted to fold into a beta-propeller domain. Using K562 alpha4 transfectants we show that mutations at alpha4 subunit residues Gly130 and Gly190 affect the conformation of this domain causing a reduction in the recognition of alpha4 by anti-alpha4 antibodies which map to the beta-propeller. The improper alpha4 conformation also led to an altered association with the beta1 subunit, and to a lack of alpha4beta1 adhesion to VCAM-1 and CS-1/fibronectin, as well as an abolishment of anti-alpha4- and anti-beta1-dependent homotypic aggregation. The total conservation of Gly130 and Gly190 among integrin alpha subunits suggests their importance in the correct folding of their respective beta-propeller domains, and thus, in the adhesive activity of the integrins.
